bow tie speculation

Notice anything unusual about the Doctor's bow tie?

After watching "The Pandorica Opens", my husband and I had to flip back to "Flesh and Stone" to see whether Pandorica Doctor matched jacket!Doctor, which he did. Red bow tie. But then we realized the Doctor's bow tie wasn't always red. So we looked at all the episodes in the series, and here's what we came up with:

Patterns, anyone? Largely, it looks like the Blue episodes tend to be the "monster of the week" ones and the Red episodes tend to be "conspiracy theory" ones - though 8&9 break that pattern. It also looks like the Blue episodes are in the past, though "The Lodger" breaks that pattern.

But most jaw-dropping was Amy's Choice, the only episode where the bow ties change color. The Leadworth!doctor has a blue bow tie. The TARDIS!doctor has a red bow tie. And the Dream Lord has a red bow tie, and so does the Waking!doctor.

And by the way, what does the TARDIS!doctor do at the end? Explode the TARDIS!